The concept of a dual articulation acetabular cup was developed by Prof. Bousquet in 1974. This concept has been shown to provide high stability after revision and primary total hip arthroplasty. The aim of our study was to evaluate the incidence of prosthetic instability in a consecutive homogeneous series of 384 primary dual mobility cups. Incidence of instability and implant survival were evaluated. Mean follow-up was 15.3 years (range, 12-20). There was no early or late instability. On the acetabular side there were 13 aseptic loosenings, 14 intraprosthetic dislocations, and seven polyethylene wear cases that required replacement of the liner. The cumulative survival rate of the dual-articulation acetabular cup using surgical revision for aseptic loosening as the endpoint was 95.9%±4.1% at 18 years postoperatively. Our series proves the good long term behaviour of dual-articulation acetabular components in primary arthroplasty. Their excellent survivorship rate and the absence of episodes of prosthetic instability increase our confidence in this concept. Résumé Le concept de cupule à double mobilité a été inventé par le Professeur Gilles BOUSQUET en 1974. Ce concept a permis de mettre en évidence une importante stabilité des hanches, notamment après révision mais également dans les prothèses totales de hanches de première intention. Le but de cette étude est d'évaluer l'incidence et l'instabilité sur une série homogène consécutive de 384 hanches traitées avec cupule à double mobilité. Le taux d'instabilité des implants sur les patients survivants a été évalué. Le suivi moyen a été de 15,3 ans (de 12 à 20 ans) au plus long recul, il n'y a aucune instabilité ni primaire, ni tardive. Par contre, il existe 13 descellements aseptiques acétabulaires, 14 luxations intra prothétiques, 7 usures du polyéthylène qui ont nécessité un remplacement du PE. Le taux de survie cumulé de cette cupule à double mobilité est de 95,9%±à 18 ans si l'on prend comme critère la révision pour descellement aseptique. Cette série prouve le bon devenir à long terme de cette articulation dans les prothèses totales primaires, avec un excellent taux de survie et l'absence de phénomènes de luxation inhérentes à ce concept.

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Salter-Harris type III and IV medial malleolar fractures (MacFarland fracture) is a joint fracture of the ankle in children. The fracture line passes through the medial part of the lower epiphyseal disk of the tibia. Prognosis is dominated by later risk of misalignment and osteoarthritis. The aim of this study was to evaluate the functional and radiological outcome of these fractures. We retrospectively analyzed the cases of 48 children with MacFarland fractures (31 boys and 17 girls), mean age at the time of trauma 11 years 6 months (range, 8-15 years). The fractures were classed into two groups according to the Salter and Harris classification for epiphyseal detachment: Salter III (30 cases) and Salter IV (18 cases). Surgical treatment was given in all cases (46 screw fixations, 2 pin fixations). Three outcome categories were used: good (no pain, no stiffness, no limp, no misalignment, no surgical complication, no healing problem), fair (pain and/or stiffness and/or limp and/or healing problem without misalignment, no surgical complication), and poor (misalignment or surgical complication). Mean follow-up was 3 years and 3 months (24-94 months). Twenty-eight children were skeletally mature at the longest follow-up. The three-month postoperative assessment showed 35 patients with good results and 13 children with fair results. Ankle stiffness was noted in 6 cases, ankle pain in 4 cases, wound healing complications in 4 cases, limp in 1 case, and snapping in 1 case. The long-term outcome was considered good for 45 patients, fair for 2 patients (1 wound adherence and 1 hypertrophic scar tissue), and poor for 1 patient (6-degree varus deformity). We did not note leg-length discrepancy or malunion at the longest follow-up. Our results show that growth arrest after MacFarland fracture is no fate. We used surgery more than is generally reported by other teams, opting for surgery as soon as the displacement was >or=1 mm. Surgical treatment was arthrotomy in all cases to achieve anatomical reduction under direct view, followed by osteosynthesis. We believe that it is difficult to evaluate if the reduction is perfect under the control of the intensifier screen alone. Arthrotomy did not lead to ankle stiffness, in any of our patients at longest follow-up.